Prenatal diagnosis of true knot of the umbilical cord.
D005260:Female; D006801:Humans; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D018615:Ultrasonography, Doppler, Color; D016216:Ultrasonography, Prenatal / Q000379:methods*; D014470:Umbilical Cord / Q000002:abnormalities / Q000000981:diagnostic imaging*